A fraction m / n is basic if m < n and it is irreducible if gcd(m, n) = 1. Given a positive integer n, in this problem you are required to find out the number of irreducible basic fractions with denominator n .
For example, the set of all basic fractions with denominator 12, before reduction to lowest terms, is
Reduction yields
Hence there are only the following 4 irreducible basic fractions with denominator 12
Input
Each line of the input contains a positive integer n (< 1000000000) and the input terminates with a value 0 for n (do not process this terminating value).
Output
For each n in the input print a line containing the number of irreducible basic fractions with denominator n
Sample Input
12 123456 7654321 0
Sample Output
4 41088 7251444
Rezaul Alam Chowdhury
“I shot an arrow into the air, It fell to earth, I knew not where; For, so swiftly it flew, the sight Could not follow it in its flight.
I breathed a song into the air,
It fell to earth, I knew not where;
For who has sight so keen and strong,
That it can follow the flight of song?
Long, Long afterward, in an oak I found the arrow, still unbroke; And the song from beginning to end, I found again in the heart of a friend.”
Source: http://uva.onlinejudge.org/external/101/10179.htmlKeyword:number theory
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